/Engine/Source/Runtime/Engine/Classes/Engine/Polys.h
Split with a Bsp node.
int32 SplitWithNode ( const [UModel](API\Runtime\Engine\UModel) * Model, int32 iNode, [FPoly](API\Runtime\Engine\Engine\FPoly) * FrontPoly, [FPoly](API\Runtime\Engine\Engine\FPoly) * BackPoly, int32 VeryPrecise ) const